Go to https://www.tradeskillmaster.com/pets/compare to compare prices of different servers. I’ve done this a lot, and I’ve bought pets for a few hundred gold on a server, transferred it to my main server and sold for 10k gold and more. You also need to buy cheap pets on your main server to transfer to other servers so that you can build up a bit of gold on other servers so that you can buy pets. World of Warcraft: Battle for Azeroth also provides you with the opportunity to quickly upgrade your character to level 110. Enter the enormous battle fully prepared for it. After you start the expansion, you will sail to the kingdom of Kul Tiras and visit the trolls of the Zandalari Empire. Win epic battles and take control over the strategically placed Stromgarde. Discover a twenty-player cooperative missions on the War Front and take part in numerous expeditions. Gather resources scattered over treacherous, undiscovered territory.

Items you buy from vendors can be resold on the auction house for a profit. The most common way of making gold this way is finding either vendors with limited supply items that you can only buy a set amount of a particular item from and then you have to wait a while before someone can buy more, or buy items from vendors located in locations that are far off. There are also vendors that will sell items for other currencies than gold. One more important thing to note is that you can sell very common easily available items on the AH as well. Like crafting materials from profession supply vendors that only cost a few copper or silver that can be resold on the AH for gold, and they actually have a decent sale rate.

Don't put all your eggs in one basket. It's a lot better to spend your working capital on buying forty items for auction, each with the potential for profit, than to take all your working capital and invest it in that one purple leatherworking recipe that you hope will make you several hundred gold. If that puppy doesn't sell, or doesn't sell for what you want, you've just wasted all your working money, and deprived yourself of a lot of flexibility. Leave speculating on purple items until you have a few thousand gold squirreled away.
To use it as an auctioneer, send all your auctionable items from your alts to your bank alt, and organize all your auctions from this character. This saves your time spent on auction house management, focuses all your income to one character and allows for easier overview of your cash flow. Consider using an alt management addon to be able to access all information about your alts from your bank character. One such addon is Altoholic

If you are just coming out of Level 110, you will probably have a number of different Legendary items to choose from. Your Legendaries' special effects will stop working at Level 116, but until then they can be a very powerful addition to help you level up quickly. These are our Legendary recommendations for leveling as a Arcane Mage in Battle for Azeroth:

These iconic locations will look a little different than what players see on the live servers. Hook Point and Mugambala on the Tournament Realm resemble marketplaces, full of vendors that will provide players with the specific gear required for MDI—the best gear from dungeons and raids, all set to item level 415—as well as pots, flasks, gems, and enchants. All a mythic dungeon-runner could desire, sold at the bargain price of zero Gold. This is to ensure that all players in the MDI race will have access to all the things they feel is the best fit for their character and for their team’s overall composition and strategy.

You will need to cover very large areas in order to get a few chests as they are quite rare. Vanilla, TBC and WotLK zones work best. The way I like to do it is to park one Rogue class trial in Outland and one in Northrend, then fly over the whole continent and look for chests. One whole run might only yield 3-10 chests but you will still make a bunch of gold as you are almost guaranteed rares in chests in these zones.